2026 GMC Sierra 1500 Owner Complaints

2026 GMC Sierra SLT with 3.0 Duramax diesel engine. While driving down the road with the cruise set to 55 MPH on 8/29/26, the engine started to run rough. I slowed down, but this did not seem to help; I sped up, and the problem persisted no matter what I did. Service traction control and service ESC displayed on the dash. I drove to the dealership; their service department was closed because it was Saturday. I took my salesman for a ride so he could witness the issue firsthand. He confirmed something was not right, and they put me into a loaner vehicle. The truck has 848 miles on it. Service diagnosed it as a fuel issue in cylinder 2, replaced the injector, but the issue did not go away. GM TAC team advised replacing the motor; that is what I am currently waiting on. The dealer has the motor and is awaiting the install.

NHTSA ID

11766683

Incident

Aug 29, 2026

While turning right and at a slight incline the truck engine turned off, the transmission made a grinding noise, the truck went into neutral and the dash stayed “Press Start Button”. This is the second time this has happened within 5000 miles of the struck being purchased. Several others have reported the exact same issue on Facebook forums.

NHTSA ID

11766519

Incident

Sep 23, 2026

Fuel Filter and High pressure Rail System The truck started shuddering and began to go into limp mode also shifted into neutral byitself No It was inspected by the dealership shop and now insurance Check engine light came on and code P1089

NHTSA ID

11766503

Incident

Aug 15, 2026

The contact owned a 2026 GMC Sierra 1500. The contact stated that while accelerating from a red light at 15 MPH, the vehicle sputtered and shook before finally moving forward. The contact stated the failure was a recurring failure. The contact associated the failure with NHTSA Action Number: EA26005 (ENGINE). The dealer was contacted. The failure mileage was approximately 160.

NHTSA ID

11765942

Incident

Sep 17, 2026

Mileage

160 mi

Engine blew on a 2026 GMC AT4X with the 6.2 motor. Has been inspected and confirmed by dealership. No warning on failure, was passing a car when power was lost and warning system said restart engine.

NHTSA ID

11765646

Incident

Aug 23, 2026

Very similar to NHTSA complaints 11752469; 
11762072
; 11761966
; 11761844; 
11755200 while turning left into my 6 degree inclined drive at a slow rate of speed under 5 mph, my 2026 GMC Sierra SLT X31 with 1500 miles suddenly slams into park and shuts down. "Press start" shows on display and am able to start the truck. Twice the "Service Transmission" light has displayed. I took it to the dealer after two incidents and they could not replicate. Since getting it back from the dealer, I've had six more incidents and am taking back to the dealer with more information for them. The last incident, I was prepared for it and felt the truck begin to shut down and slammed on the brake before it shut down.

NHTSA ID

11765513

Incident

Sep 10, 2026

The contact owns a 2026 GMC Sierra 1500. The contact stated that while at a stop light, the engine shut off to save fuel, but after releasing the brake pedal, the engine failed to restart. The contact shifted to park, and the engine restarted. The contact stated that the failure had occurred on several occasions after the fuel saving feature was deactivated. Additionally, the contact stated that the failure had occurred while slowing down and driving over a railroad track and hauling a trailer. The vehicle was taken to the local dealer on several occasions, but the failure was not duplicated. The manufacturer was notified of the failure. The failure mileage was 4,300.

NHTSA ID

11765373

Incident

Jul 16, 2026

Mileage

4,300 mi

My 2026 GMC AT4X 6.2 liter engine had a lifter fail for #5 cylinder due to a faulty designed crankshaft bearing causing a knocking with the engine running. It required the engine to be replaced by GMC at only 7100 miles. The dealership admitted it was a defective/incorrectly manufactured part that caused the failure. I wanted to report this since GMC had said this issue had been corrected on the 2026 model year engine, but I have been reading that this issue is still occurring in the new vehicles and at a very low mileage instance. Mine failed at only a little over 7,000 miles.

NHTSA ID

11765327

Incident

Jul 27, 2026

The 6.2L L87 V8 engine in my 2026 GMC Sierra 1500 suffered a sudden, catastrophic mechanical failure and shut down completely while driving at 65 mph with only 6113 miles on the odometer. There were no dashboard warning lights prior to the seizure, resulting in a sudden and dangerous loss of power. I was towing a 30 foot camper at the time and passing an 18 wheeler, it was truly a dangerous situation at the time and my wife and I feel very fortunate that we that we didn’t have a fatal accident.The dealership confirmed a total engine failure/seizure and had to replace the entire engine assembly under warranty."

NHTSA ID

11765185

Incident

May 31, 2026

The tailgate opened without my knowledge on my first drive home from the dealer. I was pulling my trailer at the time, when I backed into my driveway it pinched against the trailer and damaged the tailgate. There were no warning lights or anything to tell me it came open. The dealer examined it and found nothing wrong with the systems. It was raining on my way home and I know they've had problems with that in the past. While this incident didn't lead to any accident, it very well could have. I'm a sub-contractor, I haul a lot of tools and product that I rely on that tailgate keeping it all contained. If it comes down without any warning it could easily lead to a major accident.

NHTSA ID

11764905

Incident

May 22, 2026

The contact owns a 2026 GMC Sierra 1500. The contact stated that while hauling a trailer and making a left turn at 5 MPH, at a busy intersection, the message "Shift to Park" displayed, and the vehicle lost motive power. The vehicle was restarted. The contact stated that the failure was persistent. The local dealer was notified of the failure by phone. The vehicle was taken to the dealer, where it was diagnosed that the telematics module had failed and needed to be replaced. The vehicle was repaired. The failure mileage was approximately 3,900.

NHTSA ID

11764703

Incident

Jul 22, 2026

Mileage

3,900 mi

The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving 35 MPH, the vehicle stalled. Additionally, the wheels locked up, and transmission made a screeching sound. The contact was able to restart vehicle after approximately 5 minutes. The failure was recurrent. The vehicle was towed to the dealer, but the dealer was unable to duplicate the failure. The dealer replaced an unstated module that was damaged during the failure. The manufacturer was contacted by phone and was made aware of the failure. The failure mileage was approximately 6,000.

NHTSA ID

11764644

Incident

Aug 11, 2026

Mileage

6,000 mi

The contact owns a 2026 GMC Sierra 1500 equipped with Bridgestone Tires, Tire Line: Dueler A/T, Tire Size: 275/60/R20, DOT Number: 17XW09K63. The contact stated that the sidewall around the bead of the four tires were cracked. The tires were dry rotted. The tires were the original equipment. The dealer was notified of the failure in person. The failure mileage was approximately 13,300.

NHTSA ID

11764465

Incident

Sep 1, 2026

Mileage

13,300 mi

Catastrophic engine failure. A 2026 GMC Sierra with only 7360 miles had engine failure while driving at 45 miles per hour which resulted in no power from the engine to assist in getting the truck off the road and stopped safely out of the road. In my case, it happened late at night so traffic wasn't an issue. I was just stranded in a dark, rural area late at night. If this happens to someone in traffic, the results may be much different from mine. After this incident, I learned that this is not uncommon and many trucks/SUVs with the GM 6.2L engine have failed in the same or a similar manners and earlier models have been recalled for the same issue.

NHTSA ID

11764358

Incident

Aug 28, 2026

on Friday the 11th the vehicle quit running had to be towed and left me stranded in the middle of an intersection. This is a second vehicle from GM with the 6.2 L engine that has done this to me. The dealer says it’s catastrophic engine failure, and they’re gonna replace the engine. I was told that GM Edward repaired this issue but is still selling brand new trucks with this motor that has this failure, they can lead people stranded in very compromising positions.

NHTSA ID

11764203

Incident

Sep 11, 2026

At just below 5,000 miles of use, my new 2026 GMC Sierra At4 (6.2L V8 engine) is currently undergoing a total engine replacement arising from traces of metal being detected in the oil filter. Although covered by GMC Warranty since it is essentially a brand-new vehicle, I wanted to report this issue as it is most likely part of the large GM recall pertaining to this L87 engine since I am concerned this is related to ongoing 6.2L L87 engine failure investigation. It is expected to be out for around 4-6 weeks with a new engine incoming and would want to be covered if the new engine fails in the future with any issues relating to this case.

NHTSA ID

11764094

Incident

Sep 5, 2026

Was driving the vehicle and started making a loud knocking noise and had a loss of power.

NHTSA ID

11763861

Incident

Aug 28, 2026

The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving at various speeds, the vehicle hesitated to maintain automotive power and was a potential safety risk for his wife and children. The message "Shift to Park and Restart Vehicle” was displayed. The vehicle was shifted into park(P) and back into drive(D) as a temporary fix. The vehicle was taken to a local dealer on several occasions to be diagnosed; however, the cause of the failure was unknown. The failure mileage was approximately 700.

NHTSA ID

11763117

Incident

Jul 16, 2026

Mileage

700 mi

Rattling, knocking sound from the 6.2 ltr motor. Dealer verified engine failure, needs to be replace. Engine failed with only 4770 miles. Never made it to the first oil change.

NHTSA ID

11762965

Incident

Sep 3, 2026

Complete engine failure. Had to get the engine replaced with only 2,700 miles on it. Back in the shop on 9/5 to fix the engine again.

NHTSA ID

11762681

Incident

Aug 17, 2026

Three times this has happened. Most recently Pulling in drive and jumps out of drive to park with a jerk and stops.

NHTSA ID

11762573

Incident

Sep 5, 2026

The infotainment system keeps having the sound completely shut off. The radio, GPS, blinker system sound will not work.

NHTSA ID

11762558

Incident

Sep 7, 2026

The contact owned a 2026 GMC Sierra 1500. The contact stated that while slowly driving up a slightly inclined driveway and making a left turn, the engine shut off. The contact stated that either the parking brake activated, or the vehicle suddenly decelerated. The contact stated that the failure had occurred several times, with three identical vehicles, including the loaner vehicle provided by the dealer. During the failure, the messages, "Press Start" and "Service Transmission" were displayed. The vehicle was taken to the local dealer who was unable to determine the cause of the failure. The vehicle was not repaired. The vehicle was later traded in for an identical vehicle. The manufacturer was notified of the failure.

NHTSA ID

11762072

Incident

Jun 1, 2026

The contact owns a 2026 GMC Sierra 1500. The contact stated that while slowly driving up a slightly inclined drive port and making a left turn, the vehicle shut off and the parking brake was activated or the vehicle suddenly decelerated. The contact stated that the failure had occurred on several occasions with three separate identical vehicles, including the loaner vehicle provided by the dealer. During the failure, the messages "Press Start" and "Service Transmission" were displayed. The vehicle was taken to the local dealer who was unable to determine the cause of the failure. The manufacturer was notified of the failure. The failure mileage was 29.

NHTSA ID

11761966

Incident

Sep 3, 2026

Mileage

29 mi

The contact owns a 2026 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the transmission independently shifted to park or neutral. The contact stated that the failure had occurred while driving at slow speeds. The contact stated that during one failure, the brakes independently activated, and the vehicle shut off. The contact stated that while attempting to restart the vehicle, the vehicle started. The contact stated that the failure was persistent. The dealer was made aware of the failure by phone. The vehicle was taken to the dealer; however, the diagnostic result was not provided. The failure mileage was approximately 500.

NHTSA ID

11761844

Incident

May 1, 2026

Mileage

500 mi